A typical pneumatic fastener driving tool includes a housing having a nose portion that is located relative to a workpiece at a position where a fastener, such as a nail, is to be driven. When the tool is placed against the workpiece, a movable safety member enables a drive stroke in which a driver blade drives a fastener along a drive track through the nose and into a workpiece. Usually the tool is designed so that the fastener penetrates fully into the workpiece with the head of the fastener countersunk to some degree.
Among the many uses to which fastener driving tools have been put is the installation of siding in the construction industry. Because of its advantages over conventional wood siding and other alternative materials, preformed hardboard siding is becoming more popular. Standard nailing techniques can lead to difficulty in the installation of hardboard siding. For example, countersunk fastener heads can cause fracturing of the fibers of the hardboard material at the exposed surface and a reduction in the life of the material or its surface finish may result. In addition, hardboard siding material is designed for optimum performance with fasteners installed a predetermined distance from the edge of the siding, and carefully controlled positioning is desirable.
A typical power fastener driving tool may cause difficulties in the installation of material such as hardboard siding because the tool cannot be controlled to precisely vary fastener penetration into the workpiece. In addition, the tool cannot readily be located at a precisely determined, optimum position relative to the siding material. While a simple, fixed edge guide might be employed, this approach would limit use of the tool to a single orientation relative to the workpiece and would prevent use of the tool for other purposes or at other locations on the workpiece.